Types of ECG Machines and Difference .
Single Channel ECG Machine :
Single Channel ECG machine is basic ECG Machine that prints single ecg waveform /channel at a time. Single channel ECG machine contains one amplifier channel and one recording system. This type ECG Machine’s paper has space for only single trace at a time . Thus all 12 channels ( I,II,III, aVR, aVL, aVF and V1-V6 ) of ECG Machine report will be printed one by one on the paper.
Such Type of ECG Machine used to have a multi positioning switch, by selecting the switch the desired lead connection can be selected.
However nowadays single channel ECG machine comes with microprocessors and with automatic modes . So it will print ECG channel automatically one by one without manually changing the leads.
Most of single channel ECG machines use 50mm paper width.
BPL ECG Machine 6108 is example of the single channel ECG machine. Single ECG Machine Price range is ( USD 200 to USD500) INR 15,000 to INR 35,000
The Multichannel ECG ( 3/6/12 channel ) consists several amplifier channels and a corresponding number of recording systems . This facilitates recording of several ECG leads simultaneously and thus considerably reduces the time required to complete a set of recordings.
In Modern 3/6/12 ECG machines use microprocessor to capture the heart signals from standard 12 leads configuration, sequencing the lead selector to capture four groups of 3 lead signals and switching groups every few seconds.
3 Channel ECG Machine :
As the name suggest, 3 Channel ECG Machine print 3 waveforms/channels at a time.
In 3 channels machines the ECG signals selected by the microprocessor are amplified , filtered and sent to a 3 channel multiplexer. The multiplexed analog signals are then given to an analog to digital converter which is then stored and sent to digital to analog converter for reconstructing the analog signals and these signals are de-multiplexed and passed to the chart recorder / Printer or video display to display the same .
A three channel ECG machine print 12 waveform in 4 sections. this report format is called 3×4 format . 3 Channel ECG Machine also print a rhythm lead in some cases.
3 channel ECG Machine prints 3 waveforms at a time on the charting paper 1st section waveform ( I,II,II )
3 waveform in 2nd section ( aVR , aVL, aVF )
3 waveform in 3rd section ( V1, V2, V3 )
3 waveform in 4th section ( V4, V5,V6 )
To print all the 12 waveform it takes 4 slot on the ECG chart paper ( It is also called 3×4 format ) . below fig shows a ECG report from 3 channel ECG Machine . Print report from 3 ch ECG machine is usually longer on paper as compare to 6 channel and 12 channel ECG Machine .
Major 3 channel ECG report are usually printed on 60mm/80mm or 100mm ECG paper depending on the size of printer available in the machine . It depends on the ECG Machine model and price .
3 Channel ECG Machine Price range is (USD 350 to USD750) INR 25,000 to INR 50,000.
6/12 Channel ECG Machine :
Similarly in 6 channels and 12 channels there are 6 channels and 12 channels multiplexer in the machine. In 6 channel ECG Machine 6 waveforms are printed simultaneously . So 12 waveforms can be printed in just 2 slots of the paper ( Its format is called 6×2 format )
6 Channel ECG Machine prints 6 waveform in one go. So its paper width is wide as compare to 3 channel ECG Machine. So print format of 6 channel ECG Machine would be 6×2. 6 channel ECG Machine report length is comparatively less because page width is large. 6 Channel ECG Machine Price range is (USD 500 to USD 950) INR 35,000 to INR 65,000.
12 channel ECG Machine can print 12 waveform simultaneously. In 12 channel ECG machine all 12 channel of the ECG are printed in one slot ( so its format is called 1×12 format ).
12 channel ECG can print in 6×2 and 3×4 formats . so it is also called multichannel ECG machine. Most of 12 Channel ECG Machine are know to print ECG report on A4 size paper. and Report is wide and less in length. so is easy for Doctors to analyze and compare the ECG waveform. 12 Channel ECG machine use 210mm to 216mm wide paper.
BPL 9108 is most selling 12 channel ECG Model and Comen 1200B & Contec 1200G ECG machines are low cost and value for Money products
12 Channel ECG Machine Price range is ( USD 700 to USD 1800 or more ) INR 50,000 to INR 120,000. Some most advance 12 channel ECG machine may cost higher up-to INR 150,000.
below fig shows a print report of 12 channel ECG Machine . 12 channel ECG report are attractive in look because all waveforms can be compare simultaneously .